The scope of the present invention is link-type V-belts.
Link-type V-belts having link plates pinned together to retain the links in a continuous belt and employing transversely mounted blocks to define the V-belt configuration have been previously employed. Such an earlier device is illustrated in FIGS. 10, 11 and 12 herein. In this prior arrangement, the power transmission block a of each link is adapted to engage with a V-groove b, illustrated in phantom, as can be seen in FIG. 12. The links are defined by link plates c or d with the link plates d being nested alternately within the link plates c at attachment locations where pins e retain the links in a continuous belt. The power transmission blocks a extend through block supporting holes in the links c and d in a mounting portion of each link plate displaced laterally from between the attachment holes receiving the pins e. The power transmission blocks a include a step portion fit between the link plates c or d to retain the blocks in position in each link.
When the device illustrated in FIGS. 10, 11 and 12 is employed to transmit significant power, each of the power transmission blocks a has its end faces engaged directly and frictionally with the V-groove b. Side pressures Fi from the V-groove faces act as compressive stresses upon each power transmission block a to develop frictional forces parallel to the interface between the power transmission blocks a and the V-groove b. Thus, a tangential force Wi for transmitting power through the belt acts as a bending moment M upon each power transmission block a when positioned within the V-groove b. As a result, the power transmission blocks a directly receive the high stress composed of the compressive stresses Fi and the bending moment M. These stresses define the maximum transmission torque available with such a belt.
In order to increase the maximum driving torque which can be sustained by such a V-belt configuration, one could conceive of increasing the thickness of the power transmission block a. By doing so, however, the link plates c and d must have their dimensions correspondingly reduced in order to accommodate the limitation on space. This in turn results in a weakening of the link plates. It is also conceivable to enlarge the pitch of the belt. However, such an enlargement increases the minimum winding radius, enlarges the entire power transmission and reduces the density of contact between the pulley b and the power transmission blocks a. Clearly the various constraining requirements of such a link-type V-belt system limit the strength or effectiveness of the transmission.